Biohazard Detection Systems (BDS) have been developed for detecting biohazardous airborne particulate matter in environments that are susceptible to infiltration by such matter. A particular application of BDS is a threat detection system for postal processing machinery capable of detecting low-level releases of anthrax. A typical BDS cabinet used in conjunction with postal equipment contains within it a blower module drawing an airflow (e.g., 400 liters per minute (LPM)). The blower is used to draw air from a collection hood/manifold installed on standard mail processing equipment, or from the ambient environment.
Future hazardous material detection systems will include the ability to detect various other biological and toxic aerosol threats.
Historically, the majority of acceptance/qualification testing conducted on a typical BDS unit has required the use of operating the mail processing equipment complete with the air collection equipment. A carrier “hot” envelope that has been loaded with a weighed quantity of the hazardous material to be detected is then processed through the equipment along with other “cold” envelopes to generate background dust and particulates. Particulate emissions generated are then collected by the hood/manifold and are drawn into the BDS unit. As this is a highly dynamic system, there is no way to control the amount of target material released from the envelope for any given test, as the quantity of the release is only partially dependent on the weight of the material carried in the hot envelope. Furthermore, this testing, although adequate to meet the qualification needs of current BDS units, is limited, both in its ability to test the BDS cabinet for use in non-postal applications and in its ability to evaluate new detection technologies for use in chemical/biological detection applications.
Thus, a need exists for a system for testing and qualifying particulate detection devices that is accurate and flexible in its application to a variety of types of particulate matter for use in a variety of environments with different background clutter.